One method of producing cephalosporins used medicinally as antibiotics comprises converting cephalosporin C to 7-aminocephalosporanic acid and then acylating this product to produce the desired 7-acylamidocephalosporin. This method suffers from the disadvantage that it is necessary to first isolate and purify the intermediate 7-aminocephalosporanic acid. Accordingly, other methods have been sought which would avoid the need of preparing the 7-aminocephalosporanic acid.
More recently it has also been found that cephalosporins having a methoxy substituent in place of the hydrogen substituent at C-7 are produced by various microorganisms. These cephalosporins likewise contain an aminoadipoyl group, and it is desired to replace this aminoadipoyl group with other acyl groups in order to provide new cephalosporins of enhanced antibiotic activity.